Some interesting results on dynamic response of both systems are presented. They show significant differences between the water and oil hydraulics.
COBISS.SI-ID: 762116
The results clearly show their dependence on friction properties of selected materials in different hydraulic fluids. While the oil valve worked perfectly, water valve has some irregularity, linked with the small gap, the shape irregularity, the surface roughness and the poorer lubrication conditions in the water hydraulics compared to the oil system. However, the observed irregularity of the movement of the spool in the water hydraulic valve had almost no influence on the movement of the piston rod of the water cylinder, which is a very promising result for future research on water hydraulics
COBISS.SI-ID: 6308615
Our initial findings suggest the need for modifications to the test rig, and a comparison of the behaviour between two similar hydraulic test rigs is shown. The main parameters measured during the investigation were the pressures, the spool displacements and the responses of the piston in the double-acting hydraulic cylinder. However, transient phenomena in the water and oil hydraulic test rig were also analysed and compared. Experiments were performed on systems with and without an applied load. The results reveal very different behaviours for the oil and the water hydraulics.
COBISS.SI-ID: 10642203
We carried out preliminary tribological tests of different material-pairs lubricated with additive-free distilled water. The tested materials were stainless steel, PI, PEEK and Al2O3. The results of the preliminary tribological tests of different material pairs are described in this paper. The best material pair considering low wear and a low coefficient of friction was obtained with graphite-modified PEEK composite against Al2O3.
COBISS.SI-ID: 10167835
However, in order to ensure a satisfactory useful life time of the proportional 4/3 directional control valve, an optimal tribological pair is required in the valve. With this aim in mind, we carried out preliminary tribological tests of different material-pairs lubricated with additive-free distilled water. The tested materials were stainless steel, PI, PEEK and Al2O3. The results of the preliminary tribological tests of different material pairs are described in this paper.
COBISS.SI-ID: 10140699